Smoke-indicator.



T. W. McNEILL & I. J. BABCOCKI SMOKE INDICATOR.

APPLICATION FILED MAR. 20, I916.

Patgn'ted June 27, 1916.

THOMAS W. MCNEILL AND IRA J. BABCOCK, OF CHICAGO, ILLINOIS.

SMOKE-INDICATOR.

Specification of Letters Patent.

Patented June 2'2, 191%.

Application filed March 20, 1916. Serial No. 85,262.

, To all whom it may concern Be it known that We, THOMAS W. Mo- NEILLand IRA J. BABCOCK, citizens of the United States, all residing atChicago, in the county of Cook and State of Illinois, have inventedcertain new and useful Improvements in Smoke-Indicators, of which thefollowing is a specification.

This invention relates to improvements in smoke indicators, such as areused with fuel consuming devices to indicate the density or amount ofsmoke passing to the flue or chimney.

The invention relates more particularly to an improvement ormodification of the smoke indicators, shown in our prior Patents No.1,012,403 issued December 19th, 1911 and No. 1,103,603- issued July14th, 1914.

One of the particular objects of this invention is to provide acomparatively inexpensive apparatus such as may be quickly and easilyinstalled on a boiler setting without altering the flue structure.

Another object of the invention is to provide a smoke indicator which isreadily visible from any point in the boiler room in front of the boilerand which may be easily and readily removed should occasion demand.

Still other objects will become readily apparent to those skilled in theart from a consideration of the following description and drawings,wherein Figure 1 is a vertical longitudinal sectional view through aboiler setting showing our improved smoke indicator mounted thereon.Fig. 2 is an enlarged vertical longitudinal sectional view through thesight casing. Fig. 3 is a transverse vertical sectional view on the line33 of Fig. 2, and; Fig. 4 is a vertical sectional view through thecasing containing the source of light.

In the construction shown in our prior patents the smoke indicator isinserted in a flue passing from the boiler to the stack. Such anarrangement is sometimes objected to because of the fact that in someinstallations it is more or less diflicult to so locate the sight, oraperture through which the smoke is visible, at a point whereit iseasily viewed by the firemen. In our present invention the source oflight and the sight are s located as to utilize an opening through tlieboiler, such for example as the fire tube,

as a chamber through which the rays of light are projected onto thesight screen and in view of this we are able to mount the sight on thefront door of the smoke bOX where it is easily viewed by the firemanwithout effort. As the most commonly used type of boiler settingpositions the fire tubes at a considerable elevation above the floor, wehave found it desirable to curve the sight screen, for example, into aspherical shape, so that it may be readily visible from a distance andfrom any point in the room in front of the boiler without the necessityof provided a source of light, indicated in general by the numeral 15,and in the door. 16 carried on the front wall 11 of the setting we haveprovided a sight screen or indicator 17 in alinement with the axis ofthe same tube 14.

The lamp, or as it may be termed, the source of light, is illustrated indetail in Fig. 4, and comprises a tubular casing section 18 adapted toslide within an aperture 19 cut in the back wall 12 of the boilersetting in axial alinement with the fire tube 14. The rear end of thetube 18 is flanged out as at 21 and at one side is provided with apintle 22 on which is hinged a reflector casing 23 at the focal centerof which is mounted a source of light, in this instance, an electriclight, bulb 24. Carried by the reflector casing 23 is a transparentscreen 25 interposed between the tube 18 and the source of light. Aspring latch 26 positioned at the opposite side of the casing from thepintle 22 serves to lock the reflector casing 23 in position, as shownin Fig. 4. The tube 18 is formed with a bead 20 between which and theshoulder 21 is provided a series of perforations 27 to permit an inflowof air which reduces the amount of smoke and (lust accumulated upon thereflector 23; A ring 28 perforated to correspond to the perforations 27is slidable tapers upwardly away fromthe door to receive the wedgeshaped base 32 which 1s seamed on the rear end of the sight tube 33. Theouter end of the tube 33 is provided with apertures 34 and a slide ring35 similar to those provided on the tube 18.

A parti-spherical sight screen of translucent material 35 is mounted inan annular ring 36 which serves as a door for the outer end of the tube33, being hingedly connected thereto, as at-37. A spring latch 38 locksthe door in place as shown in Fig. 2. With the flange and beaded tubemounting the sight tube as an entirety may be quickly and easily removedwhen occasion demands, as for example, to prevent damage to the sighttube when the door 16 is swung open for inspection of the boiler.

Light emanating from the bulb 24 is reflected through the tube 14 andthrown upon the screen 35, the intensity or brillianc-y of the lightdepending, of course, on the quantity or density of smoke passingthrough the tube. As the screen 35 is curved it may readily be observedfrom any point in the boiler room greatly facilitating the work ofproperly firing the boiler.

Whereas we have illustrated and de scribed a single embodiment of ourinvention, it is obvious that various changes may be made thereinwithout departing from the spirit and. scope of the following claims.

Having described our invention, what we claim is z.-

1. The combination with a smoke indicator, of a sight opening, having acurved translucent screen.

2. The combination in a smoke indicator, of a source of light, a sighttube and a spherical, translucent screen positioned in the outer end ofthe tube.

3. The combination with a boiler setting and a boiler having a gasconducting passage extending therethrough, of a source of lightpositioned opposite one end of said passage, a sight tube positionedopposite the other end of the passage and extending to a point outsidethe boiler, and a translucent screen carried by the outer end of saidsight tube.

4. The combination with a boiler setting and a boiler having a gasconducting passage extending therethrough, of a source of lightpositioned opposite one end of said passage, a sight tube positionedopposite the other end of the passage and extending to a point outsidethe boiler, and a curved translucent screen carried by the outer end ofsaid sight tube.

5. The combination with a boiler setting and a boiler having a gasconducting passage extending therethrough, of a light reflecting surfacepositioned. at the rear of and in alinement with said passage, a sighttube positioned in alinement with and at the front end of the passage,and a curved translucent screen carried by said sight tube.

In testimony whereof we hereunto set our hands.

THOMAS MGNEILL. IRA J. BABCOCK. In the presence of FoRfiE BAIN,

MARY F. ALLEN.

